Question

integrate from 1 to 0 for 2/ (1+x^2) dx

Answer 1

\[\int\limits_1^0\frac{2}{1+x^2}\text dx\]
did you say the limits in the right order

Answer 2

yeah i did its from 0 to 1

Answer 3

\[\int\limits_0^1\frac{2}{1+x^2}\text dx\]

Answer 4

correct

Answer 5

\[=2\int\limits_{0}^{1} 1/(1+x^2) dx\]\[=[2\tan^{-1} x]_{0}^{1}\]\[=2\tan^{-1} 1 - 2\tan^{-1} 0\]

Answer 6

\[=2(\pi/4) -0\]\[=\pi/2\]

Answer 7

why is it tan?

Answer 8

http://www.maa.org/pubs/Calc_articles/ma024.pdf

Answer 9

the integration of 1/(1+x^2) with respect to x is tan^-1 x not tan x.